Plastic composite materials have been developed and used for various purposes. It remains a challenge, however, to develop bioplastic composite alternatives that would be suitable for structural building end use. For such applications a combination of features are desired, such as high strength and stiffness, low density, low cost, environmental durability, and biodegradability. A particular challenge for known bioplastic composites is that they are expensive to manufacture and generally lack sufficient durability when exposed to high humidity environments. Consequently, there is a need for composite materials that overcome these current limitations in the art. Given the vast number of possibilities for such composites and the complex and unresearched issues related to their structural properties, biodegradability, and environmental durability, the discovery of such a suitable composite material has remained an unsolved problem in the state of the art.